The invention is an improved device for transporting loads between various elevations and in particular to transporting handicapped persons in wheelchairs. Specifically, it relates to an improved device that serves a dual mission, first as a regular stairway facility for ambulatory persons, and second as a ramp-like or ramp-type facility for wheeled vehicles carrying a person or persons, or a load of freight or materials, or other similar loads. The combination stairway and ramp facility being the means by which the aforementioned loads may be moved from the level of one elevation to the level of another elevation.
Such loads in wheeled vehicles might be handicapped persons in wheelchairs, groups of people in wheeled people carriers, packaged freight or materials in wheeled truck means, or other similar loads in suitable wheeled vehicles.
The movement of such loads from one elevation to another elevation may be either an ascending movement or a descending movement.
Devices for moving the aforementioned loads between various elevations in the prior art usually consisted of elevators running vertically in a shaft-like enclosure between the various elevations or the equivalent of such vertical elevators running openly or within some restriction that might be termed an inclined elevator means. The prior art elevators running in vertical shaft-like enclosures are well known. Except for the ordinary escalator, or moving stairway, the prior art inclined elevator means are not as well known.
Some of the prior art inclined elevator means are: an inclined elevator means mounted on and along the protruding edges or nose of the treads of a stairway to one side of the stairway walking area, providing a seat or platform on which a person sits or stands while being moved; a construction type elevator having a framework set at an incline between a ground level elevation and some higher elevation, such as a roof and having a box-like corner for transporting a load from one level to the other; and an inclined set of tracks on and to which a horizontal platform is moveably affixed to ride along the tracks as a load on the horizontal platform is moved from one elevation to another by motive power means. None of these concepts of the prior art provide the novel and unique structure of the present invention for moving wheeled loads from one elevation to another.
Other prior art devices for moving wheelchairs from one elevation to another elevation are described hereinafter, usually described as stair-climbing wheelchairs.
Such stair-climbing wheelchairs consist of wheelchairs having various means affixed thereto to propel the wheelchair up the series of steps, some of which are: a tri-set of wheels rotatably at the back of the chair and a cross-type structure of small rollers at the front of the wheelchair which together drive the combination to climb the stairway; a track-like device affixed at the bottom of a wheelchair which crawls up the stairway; a set of four wheels on vertically movable supports on each side of a wheelchair with the four wheels on each side operating to individually, as a left and right pair, mount the stairs in turn while maintaining the wheelchair level; a similar device to the latter with three pairs of driving wheels on each side of the wheelchair; a track-type device which lays the track on individual treads of a stairway one after the other; and a plurality of wheels in a star-like configuration inside of a track-means that crawls up a stairway step by step.
None of the so-called stair-climbing wheelchairs of the prior art provides the novel and unique structure of the present invention for safely moving a wheelchair or other type of wheeled vehicle, as described hereinafter, from one elevation to another elevation.
The improved device of the present invention consists of a plurality of stairway treads and a plurality of stairway risers set in a first configuration of an ordinary stairway which may be used by ambulatory persons. In a second configuration the plurality of treads and the plurality of risers are stretched out, as hereinafter described, to form a straight ramp-like means up or down which wheeled vehicles, as hereinbefore described, may be moved from one elevation to another elevation.
The plurality of stairway treads and the plurality of stairway risers are suitably hinged together so that they may be stretched out into the aforementioned ramp-like means. The plurality of hinge means are each located so as to hinge the bottom or lower horizontal edge of each riser to the back or inside the horizontal edge of each riser; and the top or upper horizontal edge of each riser to the front or nose of each tread; thus providing the basic ramp-like surface when stretched out.
The top horizontal edge of the uppermost riser is similarly hinged to the horizontal front or nose of the upper landing or platform of the stairway. The bottom horizontal edge of the lowermost riser is arranged to feather-edge with the lower landing or floor when stretched into the said ramp-like configuration.
At each side of each hinge of the plurality of hinges a hinge pin-like extension protrudes beyond the sides of each riser and tread hinged combination. These hinge pin-like extensions slidably fit into slots, described hereinafter, for support of the risers and treads and for control of the movement of the combination of hinged risers and treads when changing from a stairway configuration to a ramp-like configuration or when reversing that movement.
A plurality of slots at each side of the stairway are provided in the stairway side enclosure means. The hinge pin-like extensions extend into and slidably fit in the respective slots at each hinge pin-like extension location.
The aforementioned slots provide the control of movement of the hinge pin-like extensions when the stairway configuration is changed to a ramp-like configuration or a reverse movement is made. The control of movement includes controlling the direction of movement as described hereinafter.
The aforementioned slots are so located and configured so that as the hinge pin-like extensions slidably move therein, the risers and treads are brought into the ramp-like configuration.
The slot for each hinge pin-like extension at the nose of each tread is straight and horizontal, thus the nose of the tread moves forward in a straight line. The slot for each hinge pin-like extension at the bottom of each riser rises in a gentle forward arc-like curve upwardly.
Thus, when moving into a ramp-like configuration, the nose of each tread, with the top of the adjacent riser hinged to it, moves horizontally straight outwardly to a point where the hinged joint will lie in the plane of the ramp-like surface.
Concurrently, the bottom of each riser, with the rear edge of the adjacent tread hinged to it, moves in the gentle arc of the slot to a point where this hinged joint will also lie in the plane of the ramp-like surface.
When the movement is reversed the hinge pin-like extensions follow the control slots to their original position to return the ramp-like configuration to that of a stairway.
At the lower elevation of the dual use device, as a stairway configuration and as a ramp-like configuration, a contact member is provided which is temporarily and removably affixed to the load vehicle to be elevated. The contact member is suitably hinged at one end thereof so that it can be raised to provide access to the stairway of the stairway configuration when a person desires to walk up or down the stairs.
Two power means and associated mechanisms are provided as part of the structure of the invention. A first power means is connected to a mechanism that changes the stairway configuration to a ramp-like configuration, and to reverse the operation. A second power means operates the contact member, after it is temporarily and removably affixed to the load vehicle, so as to push the load vehicle up the ramp-like surface from the lower elevation to the upper elevation; the contact member when reversed will lead the load vehicle or permit the load vehicle to move down the ramp-like surface by gravity.
It is, therefore, an object of this invention to provide a device to move wheeled vehicles from one elevation to another elevation.
It is another object of this invention to provide a device to move wheeled vehicles from one elevation to another elevation that may be operated in a stairway configuration or in a ramp-like configuration.
It is also an object of this invention to provide a device to move wheeled vehicles from one elevation to another elevation wherein the wheeled vehicle is a wheelchair.
It is still another object of this invention to provide a device to move wheeled vehicles from one elevation to another elevation wherein the wheeled vehicle is a people carrier.
It is yet another object of this invention to provide a device to move wheeled vehicles from one elevation to another elevation wherein the wheeled vehicle is a cargo carrier.
It is yet a further object of this invention to provide a device to move wheeled vehicles from one elevation to another elevation that will move the wheeled vehicles loaded or unloaded in an ascending or descending mode between elevations.
Further objects and advantages of the invention will become more apparent in light of the following description of the preferred embodiments.